This invention relates to the continuous casting of steel. It relates particularly to a synthetic slag composition used in the continuous casting of steels.
In the continuous casting of steel, it is well known that improved casting results by covering the surface of the molten steel with a protective layer of synthetic slag in the casting mold. This practice and the slags used have been described in U.S. Pat. Nos. 2,825,947, 3,315,323, 3,642,052, 3,888,294, 3,891,023, 3,926,246 and 4,102,690. The synthetic slags described in these patents are designed to (1) act as an insulating layer to prevent the molten steel for losing heat, (2) protect the molten steel from air oxidation, (3) provide lubrication and better heat transfer between the steel casting and the mold, and (4) to absorb undesirable impurities, such as aluminum oxide from the molten steel.
While there has been considerable development of synthetic slags used as described above in the open-ended continuous casting mold, there has been very little development of synthetic slags for use in the tundish in order to condition the molten steel prior to its introduction into the continuous casting mold.